Book about Firebird as basis for open documentation

Pavel Cisar wrote about his book

In 2003 I wrote a book about InterBase/Firebird in Czech. It has about
450 pages, covers the common bits and differences for InterBase 6.5/7.0
and Firebird 1.0/1.5 (not everything about 1.5 is correct, it was
published before 1.5 final release). It contains all basic stuff,
reference guide and some special topics (see the outline at the end). As
the contract with the publisher ended last year and they’re not
interested to renew it, I have all rights to (re)publish it back again.
As finding another publisher would be problematic (and it would need an
update anyway), I have thinking about releasing the manuscript under
some suitable open license for use by Firebird project. Sure, it would
need and update in some core parts and removal of references to
InterBase where they’re not relevant (not much work, I’ll do it in Czech
version), update to Reference Guide past v1.5 (already done by
documentation project, so it should be easy merge) and translation to
english.